And update on the civil war in Syria now. In the city of Aleppo, people in rebel-controlled areas say they're being bombed with new ferocity by government aircraft. Several of the crude weapons known as barrel bombs have fallen every day.

NPR's Alice Fordham is monitoring developments from Beirut. She has more on reports of an exodus from Aleppo.

UNIDENTIFIED MAN: (Foreign language spoken)

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ALICE FORDHAM, BYLINE: A barrel bomb explodes over Aleppo, in a video recorded and uploaded by activists. In the last year, the Syrian air force has frequently used these devices. Barrels stuffed with explosives and shrapnel are pushed out of helicopters and onto areas held by rebel fighters. These are not precision weapons. They sometimes even fail to detonate. But they can destroy whole apartment buildings.

In Aleppo, divided for the last 17 months between rebel and regime forces, activists say the use of barrel bombs has intensified in the last two weeks. Some tie this offensive by the forces of President Bashar al-Assad to the end of a first round of peace talks between the regime and the opposition. Others say that with shaky truces in some areas, it may be that the regime can now spare the firepower for a push to retake the city.

Either way, the effects are devastating. And the people of what was once Syria's most populous city seem to be leaving in droves. Huseyin Oruc works with a Turkish NGO, which has been monitoring the flow of refugees north toward the Turkish border.

HUSEYIN ORUC: It was around 14,000. But recently, it reached 25,000. And every day, every hours, new refugees are coming to the region.

FORDHAM: Other refugees from the violence are pushing through the last remaining crossing from rebel-held areas to the regime controlled western part of Aleppo. The numbers are difficult to verify. Jack Barsoum, an Aleppan journalist, said that local sources told him that 1,500 families came through the crossing on Tuesday. The families are now camped out in schools, he said, in relatives' houses or in the streets.

Photographs posted on opposition social media show families pushing carts laden with mattresses and cooking pots. Barsoum said they are unlikely to return home soon.

JACK BARSOUM: Because no one will know when this bombing will stop. But I think that whenever a person in Aleppo left his home, he will not come back and live in it again. Because, you know, it is a very, very dangerous area and, at the same time, thieves and burglars will leave nothing in these areas and in these homes.

FORDHAM: The government typically does not comment on military operations. As reports of the flood of refugees emerged, Syrian state media reported that there had been a celebration of President Assad in Aleppo, crowned by the unveiling of a huge portrait of him.